This unique combination of our most premium memory foams delivers a breakthrough in pressure-relieving comfort. Plus, you'll get targeted support for your back and core from extra-supportive gel memory foam placed in the middle of the mattress and more support for your whole body with a densely-packed coil design all topped with a refreshing cool-to-touch cover and a firmer feel. ComfortLoft™ Knit Cover with Chill™ and AllergenProtect™: Feel refreshing cool-to-touch comfort the moment you lie down, plus get super-soft stretch and easy care from the soft knit fabric. Plus, stay fresh and clean by protecting your mattress from common allergens, such as dust mite dander. Bring on the puppies Response™ Pro HD Encased Coils: Get even more support for your whole body with this densely-packed system of our most durable coils. Individually wrapped, they also reduce motion transfer so you'll feel less movement from your partner throughout the night. SealyCool™ Gel Memory Foam: Found in in the middle of the mattress directly under your back and core, SealyCool™ Gel Memory Foam gives you targeted support and quality, cooling comfort ComfortSense™ HD Gel Foam: Get even more personalized comfort and support with this upgraded, open-cell memory foam designed to perfectly sense and respond to your body's unique shape ComfortSense™ Gel Foam: Get personalized comfort and support as this specialty memory foam senses and responds to your body's unique shape SealyCool™ Gel Foams: Get cushioning comfort and more flexible and durable support with the cooling comfort of this gel-infused version of our high-quality traditional foam SealySupport™ Gel Foam: A version of our high-quality traditional foam, SealySupport™ is found deep down in the mattress for a unique combination of cushioning comfort and flexible support DuraFlex™ Pro Edge System: Densely-packed coils surround the edge of your mattress to create a solid seating surface, more space to sleep, and added durability. A ventilated design provides refreshing airflow. Go ahead take a seat Mattress Top Type: Tight Top Mattress Type: Innerspring Included: 1 Mattress(es), 1 Box Spring(s) Features: Cooling, Wrapped Coils, Fire Resistant, Cushioning Layer, Foam Layer Additional Information: Suitable for Adjustable Bed Frames Coil Count: 658 Coils Manufacturer Warranty: 10 Year Limited Bed Size: Twin Base Material: 100% Polyurethane Comfort Type: Firm Mattress + Box Spring Measurements: 23 Height/Inches Care: Spot Clean Certifications And Listings: Cpsc - 16 Cfr 1633 Compliant, Cpsc - 16 Cfr 1632 Compliant Country of Origin: Made in US Visit our Furniture & Mattress Customer Care Center for delivery options, protection plans and other services. Problem with an order or need help with a return? Our Furniture & Mattress Customer Service agents will be happy to help. Give us a call at 1-800-442-7902 Don’t forget to print off your delivery checklist to avoid any delays or issues when delivering your item. Set includes mattress plus box spring/foundation. King and Cal. King mattress sets feature 2-piece side-by-side foundations for easier navigation in tight spaces. This mattress meets the requirements of 16CFR Part 1632 (federal flammability (open flame) standard for mattresses and mattress pads This mattress meets the requirements of 16CFR Part 1633 (federal flammability (open flame) standard for mattress sets) when used with foundation